Apparatus and method for ionic contaminant removal in liquids

Abstract

The present application provides an apparatus for removal of an ionic contaminant from a liquid comprising a branched polymer, a filtration membrane, and a filter casing. The application also provides a method of removing an ionic contaminant from a liquid, the method comprising directing ion-contaminated liquid into and draining treated liquid from an apparatus as described in the instant specification.

1 . An apparatus for removal of an ionic contaminant from a liquid comprising:
 a branched polymer;   a filtration membrane; and   a filter casing.   
     
     
         2 . The apparatus of  claim 1 , wherein the branched polymer comprises a backbone with a degree of polymerization of about 5 to about 800 or wherein the branched polymer comprises a molecular weight of about 5,000 to about 1,000,000 Da. 
     
     
         3 - 4 . (canceled) 
     
     
         5 . The apparatus of  claim 1 , wherein the branched polymer comprises a dendrimer or a hyperbranched polymer. 
     
     
         6 . The apparatus of  claim 1 , wherein the branched polymer comprises a primary amine, a secondary amine, a tertiary amine, a quaternary amine, or a combination thereof. 
     
     
         7 . (canceled) 
     
     
         8 . The apparatus of  claim 1 , wherein the branched polymer comprises a perchlorate ion binding site. 
     
     
         9 . The apparatus of  claim 8 , wherein the perchlorate ion binding site comprises tributyl ammonium chloride, triethyl ammonium chloride, trimethyl ammonium chloride, or a combination thereof. 
     
     
         10 . The apparatus of  claim 8 , wherein the perchlorate ion binding site has a stronger binding affinity for perchlorate ions than for nitrate ions, or wherein the perchlorate ion binding site has a stronger binding affinity for perchlorate ions than for sulfate ions. 
     
     
         11 - 12 . (canceled) 
     
     
         13 . The apparatus of  claim 1 , wherein the filtration membrane comprises pores having a pore size from about 5 kDa to about 30 kDa. 
     
     
         14 . The apparatus of  claim 1 , wherein the filtration membrane comprises about 0.01 mg to about 10 mg of a branched polymer per square centimeter of membrane. 
     
     
         15 . The apparatus of  claim 14 , wherein the filtration membrane comprising the branched polymer has a total capacity for perchlorate ion of at least about 1 milli equivalents. 
     
     
         16 - 19 . (canceled) 
     
     
         20 . The apparatus of  claim 1 , wherein the filter casing is fluidly connected to a water faucet, a refrigerator water filter, a water filtration pitcher, or a combination thereof; and wherein the filter casing comprises an inlet or an outlet for regeneration fluids. 
     
     
         21 . (canceled) 
     
     
         22 . A method of removing an ionic contaminant from a liquid, the method comprising:
 directing ion-contaminated liquid into an apparatus, the apparatus comprising:
 a branched polymer; 
 a filtration membrane; and 
 a filter casing, wherein the filter casing comprises a first opening for admitting liquid and a second opening for releasing liquid; 
   contacting the ion-contaminated liquid with the branched polymer and directing the ion-contaminated liquid through the filtration membrane to produce a treated liquid; and   draining the treated liquid from the apparatus through the second opening.   
     
     
         23 - 36 . (canceled) 
     
     
         37 . The method of  claim 22 , further comprising the step of regenerating the filtration membrane and branched polymer. 
     
     
         38 . The method of  claim 37 , wherein regenerating comprises exposing the filtration membrane and branched polymer to a saline solution. 
     
     
         39 . The method of  claim 38 , wherein the saline solution comprises less than about 1 M sodium chloride. 
     
     
         40 . (canceled) 
     
     
         41 . The method of  claim 22 , wherein the filter casing is fluidly connected to a water faucet, a refrigerator water filter, a water filtration pitcher, or a combination thereof. 
     
     
         42 . The method of  claim 22 , wherein the filter casing further comprises a third opening for the release of membrane regeneration fluids. 
     
     
         43 . The apparatus of  claim 1 , wherein the liquid comprises water, and wherein the ionic contaminant comprises the a perchlorate ion. 
     
     
         44 . (canceled) 
     
     
         45 . The method of  claim 22 , wherein the ion-contaminated liquid comprises perchlorate ion-contaminated water. 
     
     
         46 . (canceled) 
     
     
         47 . The method of  claim 22 , wherein the treated liquid contains less than about 24.5 parts per billion of perchlorate ion. 
     
     
         48 . (canceled)